Assassins spared the Templars because killing their masters was unprofitable

Evidence

The second comes from a European source. When the Assassins, that is to say the group in Syria to which the name was first applied, terrorized both the Crusaders and the Muslim princes, they nevertheless spared and even paid tribute to the two Christian knightly orders, the Knights Templar and the Knights Hospitaler. The medieval French historian Joinville explains why. Speaking of the head of the Assassin order he says: “He paid tribute to the Templars and to the Hospitalers because they feared nothing from his Assassins, since the leader of the Assassins could gain nothing if he caused the Master of the Temple or the Master of the Hospital to be killed; for he knew very well that if he had one killed another just as good would replace him, and for this reason he did not wish to lose assassins where he could gain nothing by it.” — Bernard Lewis, From Babel to Dragomans, 561

Categorization

• XREF: The assassins’ own cost-benefit logic undercuts the terrorized-medieval-Europe stereotype; pairs usefully with analyses of representation vs. self-understanding in Orientalist sources.
• CANDY: The Assassins paid tribute to the Knights Templar because beheading their Master would simply produce an equally good replacement — a tidy cost-benefit account of assassination’s limits.
• SHARE: For anyone into the Crusades or the Assassin legend: Joinville’s account shows the order’s leader reasoning in cool fungibility terms about the Templar/Hospitaler leadership.